U.S. patent application number 10/435727 was filed with the patent office on 2003-12-04 for compressible foot plate to monitor pressure.
Invention is credited to Danielsson, Barbro, Gaulitz, Arne, Nicklasson, Thomas, Willen, Jan A.G..
Application Number | 20030225327 10/435727 |
Document ID | / |
Family ID | 20281785 |
Filed Date | 2003-12-04 |
United States Patent
Application |
20030225327 |
Kind Code |
A1 |
Willen, Jan A.G. ; et
al. |
December 4, 2003 |
Compressible foot plate to monitor pressure
Abstract
A compressible footplate for a device for complementary
examination of the lumbar region at computer tomography and
magnetic resonance tomography, whereby it comprises a resting plane
being part of a patient table, a footsupport being arranged to the
resting plane comprising at least one compressible footplate. The
compressible footplate comprises a footplate, a compressible means,
an indication means and a holder-on, preferable in the form of an
outer house.
Inventors: |
Willen, Jan A.G.;
(Krikonvagen, SE) ; Gaulitz, Arne; (Bolldals
Aspvagen, SE) ; Danielsson, Barbro; (Almvagen,
SE) ; Nicklasson, Thomas; (Kuttervagen, SE) |
Correspondence
Address: |
Samuels, Gauthier & Stevens LLP
Suite 3300
225 Franklin Street
Boston
MA
02110
US
|
Family ID: |
20281785 |
Appl. No.: |
10/435727 |
Filed: |
May 8, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10435727 |
May 8, 2003 |
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PCT/SE01/02502 |
Nov 12, 2001 |
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Current U.S.
Class: |
600/415 ; 378/20;
378/209 |
Current CPC
Class: |
A61B 6/0421 20130101;
A61B 6/506 20130101; A61B 5/055 20130101 |
Class at
Publication: |
600/415 ;
378/209; 378/20 |
International
Class: |
A61B 005/05; A61B
006/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 13, 2000 |
SE |
0004130-1 |
Claims
1. Compressible footplate for a device for complementary
examination of the lumbar region at computer tomography and
magnetic resonance tomography, whereby it comprises a resting plane
being part of a patient table, a footsupport being arranged to the
resting plane comprising at least one compressible footplate (1),
whereby the compressible footplate comprises a footplate (1), a
compressible means (2), an indication means (3) and a holder-on,
preferably in the form of an outer house (4), characterized in that
the compressible device comprises at least four plates having a
higher hardness (41, 42, 43, 44) and at least two plates (45, 46)
having lower hardness than the first mentioned plates, and at least
two distance means (47, 48), whereby said plates (41, 42, 43, 44,
45, 46) and distance means (47, 48) are arranged in such a way in
relation to each other that two parallel plates (45, 46) having a
lower hardness contributes to said device being compressible.
2. Device according to claim 1, characterized in that the distance
means (47, 48) have sides provide with semi-circular recesses with
a substantially circular or oval cross-section or the similar,
which are turned inward towards each other in a mounted position of
the compressible means (2) in order to create better compression
properties and a higher resistance.
3. Device according to claim 1, characterized in that an indicator
means (3) comprises at least two rolls (25, 26), an adjustable
slide (22), an elastic band (27), and a wire (28), which are
arranged to counteract each other, a pointing means (29), whereby
said indicator means (3) is arranged to influence an outer
movement/force and to transform the outer movement/force to a value
via a display unit (59).
Description
DESCRIPTION
[0001] 1. Technical Field
[0002] The present invention relates to a device comprising a
compressible footplate having an indicator means and a display unit
suitable to be used in a device for complementary examination of
the lumbar region at computer tomography and magnetic resonance
tomography.
[0003] The object of the present invention is to obtain a footplate
for monitoring pressure, the indication of said footplate being
independent from of where and how the pressure is applied, which
footplate is suitable to be used in a device with the help of which
a careful and reproducible examination of the lumbar region in
connection with computer tomography and magnetic resonance
tomography can be carried out, in particular for the diagnosis of
changes of the spinal cord and its nerve structures (spinal
stenosis).
BACKGROUND OF THE INVENTION
[0004] Traditionally, patients have been examined in a relaxed
position on their backs at computer tomography and magnetic
resonance tomography, which means that structures in connection
with the spinal cord channel, which are variable, e.g.,
intervertebral discs, ligaments, and small joints, are subject to a
minimal load. At load i.a., the pressure in the intervertebral disc
will increase, which results in a protuberance, which in turn
reduces the space in the spinal cord channel where nerve and vessel
structures available are present. At the examination of the spinal
cord channel of the lumbar region using computer tomography or
magnetic resonance tomography suspecting spinal stenosis there is a
demand for being able to load the lumbar region in the same way as
takes place when standing right up, simultaneously as the patient
is placed in horizontal position.
[0005] In U.S. Pat. No. 3,629,581 a device is disclosed for
positioning a patient's shoulders in connection with an X-ray
examination of a patient's spine, whereby the upper vertebral
column is pressed down towards the examination table and
facilitates a good X-ray imaging of the upper vertebras. Hereby a
pressure is applied over the vertebral column of the lying patient
by means of two flexible traction lines provided with handles for
the patient, which traction lines are arranged around a
footplate.
[0006] In EP-A-0 714 265 a device for the compression of the lumbar
region for medicinal imaging is disclosed, comprising a resting
plane to which a foot support is applied containing pressure
sensors arranged to register the pressure from the respective foot
on said footplate, a waistcoat arranged to be placed around the
body of a patient, traction lines being arranged between said
footplate and said waistcoat, as well as a straining device to said
traction lines, which device is arranged to be strained to a
predetermined value.
[0007] The design of the footplate can be directly connected to
lack of carefulness of the determination result, whereby there is a
problem present at the design of a compressible footplate which
indicates a pressure thereon independent of where and how the
pressure is applied onto the footplate, which can used in a device
which can be utilised at the examination of the spinal cord channel
of the lumbar region.
[0008] 2. Description of the Present Invention
[0009] The present invention encompasses a pressure footplate
suitable for reproducible indication in a device for the
compression of the lumbar region for the medical imaging. Besides
waistcoat, traction lines and a resting plane a footplate is to be
included which to a considerably degree contributes to the
carefulness of said device for the compression of the lumbar
region.
[0010] The compressible footplate comprises a footplate, a
compressible device, an indicator means, and an outer house and the
Cupertino thembetween, i.e., both the constructions of the same,
and wherein the fitting and the mounting of the compressible
footplate determine the carefulness of the final determination
result.
DETAILED DESCRIPTION OF THE INVENTION
[0011] The present invention relates to a compressible footplate of
a device used at complementary examination of the lumbar region at
computer tomography, whereby it comprises a resting plane being
part of a patient table, a foot support arranged to said resting
plane said support comprising at least one compressible footplate,
whereby the compressible footplate comprises a footplate, a
compressible device, an indicator means and a contra support,
preferably in the form of an outer house, which is characterized in
that the compressible device comprises at least four plates having
a higher hardness and at least two plates having lower hardness
than the first mentioned plates, and at least two distance means,
whereby said plates and distance means are arranged in such a way
in relation to each other that the two parallel plates having a
lower hardness contributes to said device being compressible.
[0012] According to a preferred embodiment of the invention the
distance means have sides provide with semi-circular recesses with
a substantially circular or oval cross-section or the similar,
which are turned inward towards each other in a mounted position of
the compressible device in order to create better compression
properties and a higher resistance.
[0013] According to another preferred embodiment of the invention
an indicator means comprises at least two rolls, an adjustable
slide, an elastic band, and a wire, which are arranged to
counteract each other, a pointing means, whereby said indicator
means is arranged to influence an outer movement/force and to
transform the outer movement/force to a value via a display
unit.
DESCRIPTION OF THE FIGURES
[0014] FIG. 1a shows a side view of an embodiment of a complete
device for compression of the lumbar region for medical imaging and
with the footplate seen in its environment.
[0015] FIG. 1b shows a side view of an enlargement of the footplate
with its ingoing details.
[0016] FIG. 2 shows a view of the footplate seen from above.
[0017] FIG. 3 shows a side view of the compressible device.
[0018] FIG. 4 shows an indicator means seen in a cross-section from
above and from the side.
[0019] FIG. 5a shows the outer house seen from above.
[0020] FIG. 5b shows the outer house seen from below.
PREFERRED EMBODIMENT
[0021] The compressible footplate seen in its environment is a
complete device for the compression of the lumbar region for a
medical imaging, cf. FIG. 1a.
[0022] The device, i.e., the compressible footplate comprises a
footplate 1, a compressible means 2, an indication means 3 and an
outer house 4, cf. FIG. 1b.
[0023] The footplate 1 has a substantially rectangular form having
rounded short ends, cf. FIG. 2. The front side of the footplate 1
is a contact surface of a patient's foot. On the rear side of the
footplate 1 the compressible means 2 is arranged, which in a
mounted condition is covered by the outer house 4 of the device,
cf. FIG. 1b.
[0024] On the outmost end of one of the rounded short sides of the
footplate 1 there is a protrusion 5 and screw hole 6 arranged for
an adjustable screw, cf. FIG. 1b, which will be described more in
detail in the following.
[0025] In a preferred embodiment the compressible means 2
encompasses four hard discs 41, 42, 43, 44, two bendable discs 45,
46, two distance means 47, 48, one stability washer 38 and a number
of fastening elements, cf. FIG. 3.
[0026] Further in a preferred embodiment all four hard discs 41,
42, 43, 44 have a substantially right-angled triangular form and
are preferably of the same size. One of the right sides of the
triangularly shaped, hard discs, i.e., one cathetus, s about 4
times longer than the other right side, i.e., than the other
cathetus. A somewhat convex protuberance is arranged longitudinally
along the edges of the right sides of the lower and upper hard
discs 41, 42, 43, 44. This creates a better fitting when mounting
when the somewhat convex edges will be pressed out rectilinearly
when they are fixed to the footplate 1 and the outer house 4.
[0027] The two bendable plates 45, 46 have a substantially oblong,
rectangular form and are of the same size.
[0028] The two distance washers 47, 48 have both a designs as right
block. In a particularly preferred embodiment the two distance
washers 47, 48 are provided with each their side with a semi
circular recess with a circular or oval cross-section or the
similar to create a better strength at compression of the
compressible means 2, FIG. 3.
[0029] At the mounting of the compressible means 2 onto the
footplate 1 two 41, 42 of the four hard discs 41, 42, 43, 44 are
arranged on their ends having the longer right sides as contact
surface with the footplate 1, and are arranged on a distance from
each other, and substantially parallel to each other.
[0030] A fixation of the two hard discs 41, 42 on the footplate 1
is carried out by means of two protrusions 7, 8. The protrusions
7,8 are arranged on the footplate 1 in such away that they are
arranged on either side of the said hard discs 41, 42 when these
are arranged on end on the footplate 1. In a lateral view the
protrusion 7, 8 have a substantially triangular, right-angled
form.
[0031] In the highest points of said protrusions 7, 8 there are
through-going holes 9, 10 being arranged. The two hard discs 41, 42
are arranged with fitting holes 49, 50 for the arrangement of a
through-going fixation joint, i.e., to fixedly secure the two said
hard discs 41, 42 onto said footplate 1.
[0032] The compressible means 2 further comprises two distance
washer 47, 48. The first one 47 is arranged by means of a joint
between two of the vertical side surfaces of the distance 47 to the
two pointed upper, inner situated corners of the two first hard
discs 41, 42, when these are arranged on end, cf. FIG. 3.
[0033] On the underneath side of the distance 47 there is a surface
of an end of the first bendable plate 45 being arranged, which then
is situated above the first bendable plate 45 and the footplate 1,
and is substantially parallel to both the first bendable plate 45
and the footplate 1. A second distance 48 is arranged vertically in
a corresponding manner by means of a joint between the upper and
lower sides respectively, of opposite ends of the two bendable
plates 45, 46, cf. FIG. 3. The third and forth hard discs 43, 44
are arranged on end, however, in such away that they are reversed
in relation to the first and second hard discs 41, 42. The vertical
side surfaces of the distance 48 are joined to the pointed lower,
inner corners of the hard discs 43, 44 when they are arranged on
end in accordance with above, cf. FIG. 3.
[0034] A stabilization washer 38 is arranged in an oblong rounded
through-going hole 55,56 in the upper part of each of the two upper
hard discs 43, 44 to create further stability of the compressible
means 2. In the centre of the stability washer 38 a screw hole 39
is arranged for a fixed mounting to the outer house 4 at the
mounting thereof, which will be described more in detail in the
following.
[0035] Hard discs, bendable discs and distances are preferably
fixedly arranged and joined to each other by means of an adhesive
which is then temperature hardened. The edges between distance and
hard disc, and between distance and bendable disc, respectively,
are bevelled for the purpose of obtaining a better strength when
sharp fillet joints are avoided. The sides of the distances 47, 48
having semi-circular recesses are turned inward towards each other
in a mounted position of the compressible means 2 to create better
compression properties and to obtain a better strength, cf. FIG.
3.
[0036] In two through-going holes 51, 52, and 53, 54, preferably
arranged in the same manner of the two hard discs 41, 42, and 43,
44, respectively, and in accordance with the holes of the
respectively distance 47, 48 there is shaft, screw or the similar
used as a further fastening element besides the adhesive.
[0037] When the footplate 1 is pressed in a preferred embodiment
this leads to that the first bendable plate 45 is bent in such away
that it will come closer to the rear side of the footplate 1 at the
compression. The second bendable plate 46 is then bent in a similar
way so that it will come closer to the bendable plate 45 and the
footplate 1. Thus it is substantially the bendable plates 45, 46
which are bent at the compression, which leads to that it is
primarily the bendable plates 45, 46, the second distance 48, and
the upper two hard discs 43, 44 which are moved out of their
starting positions and closer to the rear side of the footplate 1.
Accordingly, the third and fourth hard discs 43, 44 are brought
closer to the first and second hard, rigid discs 41, 42 at the
compression, so that the gap present at a non-compressed condition
is reduced during compression.
[0038] In a particularly preferred embodiment the four vertical,
triangular discs 41, 42, 43, 44 are suitably made of glass fibre
reinforced, hardened polymer, and the two horizontal, rectangular
plates 45, 46 are preferably made of a carbon fibre reinforced
polymer, such as KEVLAR.RTM..
[0039] The distances 47, 48 are preferably made of a hardened
polymer.
[0040] Concerning the footplate 1 it is arranged with two further
oblong angular protrusions 11, 12, which are arranged perpendicular
to the first protrusions 7, 8. The two shorter protrusions 11, 12
contributes to that a perfect fitting is obtained between the
footplate 1 and the outer house 4 of a mounted device, which will
be discussed more in detail in the following.
[0041] The footplate 1 is preferably made of hardened polymer, such
as polyurethane.
[0042] The task of the indication means 3 is to indicate a
compression of the compressible means 2 and to transfer that to a
readable value. The indication means 3 comprises a bottom plate 20,
an upper spherical lid 21, a slidable slide 22, two rotating rolls
25, 26, an elastic band 27, a thread 28, and a pointer 29, cf. FIG.
4. In a preferred embodiment the bottom plate 20 abuts a side
surface of the outer house 4 and the upper spherical lid 21 is
arranged on top of the bottom plate 20. A slide 22, preferably in
the form of a disc can slide along two tracks 23, 24, which are
formed inside the indication means 3 between the bottom plate 20
and the upper spherical lid 21, and perpendicular to a surface 58
where a display unit 59 is arranged. On one of the edges of the
slide 22 there is a protrusion 31, as well, having a smooth side
surface 32 arranged perpendicular to the sliding direction of the
slide 22, cf. FIG. 4.
[0043] The indication means 3 comprises in a mounted condition the
two rolls 25, 26, as well. The first roll 25 is made rotating
around its axis and is arranged parallel to the slidable slide 22,
and perpendicular to the surface 58 of said display unit 59. The
second roll 26 is rotating around its axis, as well, and is
arranged perpendicular to the first roll 25, and parallel to the
slidable slide 22, cf. FIG. 4. Both rolls 25, 26 are rotating
around their axis in both directions within the indication means
3.
[0044] In a preferred embodiment a first end of an elastic band 27
is fixedly arranged in the end of the slide 22 facing the
protrusion 31, cf. FIG. 4. A second end of the elastic band 27 is
fixedly arranged to the outer surface of the first roll 25 with an
extension via the second roll 26. When both rolls 25, 26 are
rotating the elastic band 27 slides from the first roll 25, via the
second roll 26, and towards the end position of the slidable slide
22, and back to its starting position after compression.
[0045] The said elastic band consists, preferably, of a silicon
rubber or the similar. Further, in said embodiment a first end of a
thread 28, substantially without elasticity, is fixedly arranged
with its one end to a part of the smooth surface 32 of the slide
and with a second end fixedly arranged to the outer surface of the
first roll 25 with an extension via the second roll 26. When the
two rolls are rotating the thread 28 slides from the first roll 25,
via the second roll 26, and to the second end position at the
protrusion 31 of slidable slide 22 and back to its starting
position after compression.
[0046] Both the elastic band 27 and the thread 28 are fixedly
arranged to the envelope surface of the first roll 25. They are,
however, arranged in substantially opposite side to each other and
in opposite directions to each other over the first 25 and second
roll 26. At a compression of the footplate 1 this leads to that the
elastic band 27 and the thread 28 contracts each other.
[0047] In a preferred embodiment one of the sliding directions of
the slide 22 is restricted by said protrusion 31, and its second
sliding direction is restricted by the smooth surface 32 of the
slide 22 when the device has been mounted.
[0048] Further the indication means 3 comprises a pointer 29 which
is fixedly arranged to the first roll 25 and is preferably fixedly
surrounding its envelope surface. The pointer 29 is arranged
parallel to and in close vicinity to the surface of the display
unit in order to avoid parallax effect.
[0049] In a particularly preferred embodiment rotation of the roll
25 around its axis within the indication means 3 leads to a
deflection of the pointer 29. The deflection can be read on the
display unit 59, when the angle, as the pointer 29 moves, when the
first roll 25 rotates corresponds to one scale deflection, cf.
FIGS. 4 and 5b. The pointer can also be connected to a monitoring
unit for monitoring the value obtained. The components of the
indication means are preferably made of hardened polymer.
[0050] The are also other embodiments of the indication means,
which then can be applied in a different way in relation to the
display units and pointers.
[0051] The outer surrounding house 4 of the device for compression
of the lumbar region is arranged with a space 61 for applying the
compressible means 2 and has a recess 62 for receiving the
footplate 1, cf. FIG. 5b.
[0052] The space 61 is arranged with tracks 63, 64 for receiving
the edges of the upper hard discs 43, 44 of the compressible device
4 and with tracks 65, 66 for the said shorter protrusions 11, 12 of
the footplate 1. All said tracks of the outer house 4 creates a
substantially perfect fitting in a mounted condition of the device,
which thereby leads to that the device for compression of the
lumbar region carries out very careful measurements.
[0053] In connection to the space 61 and the recess 62 two further
tracks 67, 68 are arranged to be fit in with the two protrusions 7,
8 of the footplate 1.
[0054] There is a suitable clearance between the outer side edges
of the footplate 1, and its rear side and the inner edges of the
space 61 and the recess 62 of the outer house 4 so that these parts
can move freely at a compression of the footplate 1 and the
compressible means 2. In a preferred embodiment a distance remains
of about 4 mm between the footplate 1 and the surface of the recess
62 of the outer house 4 at a complete compression.
[0055] There are other embodiments of the outer house 4, which,
however, preferably has a function as a counter holder-on to the
footplate 1 and the compressible means 2. Fixation between the
footplate 1 and the compressible means 2 has been discussed
previously. The outer house 4 and the compressible means 2 are, in
turn, fixedly arranged by means of fastening elements through a
through-going screw hole of the lower space 61 of the outer house 4
and through a screw hole 39 of the stability washer 38 of the
compressible means 2. There is then a good fitting between the
upper hard discs 43, 44 and the inner tracks 63, 64, and the
protrusions 11, 12 of the footplate 1 and the tracks 65, 66 of the
outer house 4.
[0056] On a side surface 57 of the outer house 4 the indication
means 3 is arranged by means of fastening element and is arranged
perpendicular to a surface 58 where a display unit 59 is applied,
which is previously mentioned. A suitable gap can be arranged
between the inner side of the spherical lid 21 and the surface 58,
as well, where the display unit 59 is arranged.
[0057] A hole is furthermore arranged in the outer house 4 for the
movement of the slidable slide 22 and the protrusion 31, and to
create a firm abutment between the protrusion 31 of the slide 22
and the protrusion 5 of the footplate 1.
[0058] The said protrusions 31, 5 are surrounded by an O-ring at
the mounting for a substantially exact abutment surface without any
clearance between the footplate 1, the compression means 2, the
indication means 3 and the outer house 4, which is required for a
careful calibration.
[0059] The material of the outer house 4 is preferably hardened
polymer. The O-ring is preferably of an elastic rubber
material.
[0060] In a particularly preferred embodiment adjustment and
calibration are carried out by means of an adjustment screw, which
is arranged in the screw hole 6 of the footplate 1, as previously
mentioned. The adjustment screw is arranged with its point against
the said smooth surface 32 of the slidable slide 22. When the
pointer 29 is adjusted to a zero-position on the display unit 59
the point of the adjustment screw is brought into contact with the
smooth surface 32 of the slide 22, however, without forcing this
out of its position. The smooth surface 32 then functions as a
calibration and stop surface.
[0061] The function of the compressible footplate will now be
described more in detail. When the footplate 1 is compressed and
the compressible means subsequently is compressed, then the
adjustment screw of the footplate 1 is pressed against the smooth
surface 32 of the slide 22. Then the slidable slide 22 is pressed
further into the tracks 23, 24. The slide 22 forces by means of the
elastic band 27 the first roll 25 via the second roll 26. Then the
first roll 25 rotates a certain angle around its axis whereby the
pointer 29 provides an angle deflection, which can be read on the
display unit 59.
[0062] When a patient's foot still no longer compresses the
footplate 1 the O-ring contributes to returning the slide 22 to its
starting position. The thread co-operates with the second roll 26,
when it slides and drives thereby the first roll 25, which rotates
to its starting position, whereby the pointer 29 is returned to its
starting position.
[0063] One may also consider embodiments of the invention both with
regard to the footplate 1, the compressible means 2, the indication
means 3 and the outer house 4.
[0064] Finally, it is noted that the invention can be utilized for
other compressible discs in connection with other applications.
* * * * *